Variational time discretization for mixed finite element approximations of nonstationary diffusion problems
-
Markus Bause [1] ; Uwe Köcher [1]
-
[1] Helmut Schmidt University, University of the Federal Armed Forces Hamburg, Germany
-
- Localización: Journal of computational and applied mathematics, ISSN 0377-0427, Vol. 289, Nº 1 (1 December 2015), 2015, págs. 208-224
- Idioma: inglés
- DOI: 10.1016/j.cam.2015.02.015
- Enlaces
-
Resumen
We develop and study numerically two families of variational time discretization schemes for mixed finite element approximations applied to nonstationary diffusion problems. Continuous and discontinuous approximations of the time variable are encountered. The solution of the arising algebraic block system of equations by a Schur complement technique is described and an efficient preconditioner for the iterative solution process is constructed. The expected higher order rates of convergence are demonstrated in numerical experiments. Moreover, superconvergence properties are verified. Further, the efficiency and stability of the approaches are illustrated for a more sophisticated three-dimensional application of practical interest with discontinuous and anisotropic material properties.
